I've always purchased another brand of magnesium glycinate and have never had any problems taking right before bed. I bought this brand because it was cheaper and had the "glycine" in the name and have had an upset,cramping, and sour stomach ever since. These pills are very very bitter too. I've noticed also that when I take this brand I can't take an occasional ibuprofen for my arthritis without paying the price of all day stomach cramps the next day. Switching back to my old more expensive brand! I think it did a real number on my stomach lining!

It is difficult to find a readily bio-available form of magnesium. This is very well priced and the same bio-avaiability as more expensive products such as that from Metagenics. I will buy again. Excellent for migraineurs.